J/ApJ/897/159 Type Ia supernova SN 2019ein UBVgri photometry (Pellegrino+, 2020)
Constraining the Source of the High-velocity Ejecta in Type Ia SN 2019ein.
Pellegrino C., Howell D.A., Sarbadhicary S.K., Burke J., Hiramatsu D.,
McCully C., Milne P.A., Andrews J.E., Brown P., Chomiuk L., Hsiao E.Y.,
Sand D.J., Shahbandeh M., Smith N., Valenti S., Vinko J., Wheeler J.C.,
Wyatt S., Yang Y.
<Astrophys. J., 897, 159 (2020)>
=2020ApJ...897..159P 2020ApJ...897..159P
ADC_Keywords: Supernovae; Photometry, UBVRI
Keywords: Type Ia supernovae ; Supernovae
Abstract:
We present multiwavelength photometric and spectroscopic observations
of SN 2019ein, a high-velocity Type Ia supernova (SNIa) discovered in
the nearby galaxy NGC5353 with a two-day nondetection limit. SN
2019ein exhibited some of the highest measured expansion velocities of
any SNIa, with a SiII absorption minimum blueshifted by 24000km/s at
14days before peak brightness. More unusually, we observed the
emission components of the PCygni profiles to be blueshifted upward of
10000km/s before B-band maximum light. This blueshift, among the
highest in a sample of 28 other SNeIa, is greatest at our earliest
spectroscopic epoch and subsequently decreases toward maximum light.
We discuss possible progenitor systems and explosion mechanisms that
could explain these extreme absorption and emission velocities. Radio
observations beginning 14days before B-band maximum light yield
nondetections at the position of SN2019ein, which rules out symbiotic
progenitor systems, most models of fast optically thick accretion
winds, and optically thin shells of mass≲10-6M☉ at radii
<100au. Comparing our spectra to models and observations of other
high-velocity SNeIa, we find that SN2019ein is well fit by a
delayed-detonation explosion. We propose that the high emission
velocities may be the result of abundance enhancements due to ejecta
mixing in an asymmetric explosion, or optical depth effects in the
photosphere of the ejecta at early times. These findings may provide
evidence for common explosion mechanisms and ejecta geometries among
high-velocity SNeIa.
Description:
We began daily photometric follow-up observations of SN2019ein
starting on 2019 May 2 with the Global Supernova Project using Las
Cumbres Observatory (LCO). UBV-band photometry was calibrated to Vega
magnitudes using Landolt standard fields, while gri-band photometry
was calibrated to AB magnitudes using the Sloan Digital Sky Survey
(SDSS).
Objects:
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RA (2000) DE Designation(s)
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13 53 29.13 +40 16 31.3 SN 2019ein = SN 2019ein
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablea1.dat 97 56 Optical Photometry of SN 2019ein
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See also:
II/183 : UBVRI Photometric Standards (Landolt 1992)
VII/233 : The 2MASS Extended sources (IPAC/UMass, 2003-2006)
J/AJ/131/1648 : Type Ia supernovae at high and low redshifts (Blondin+,2006)
J/ApJ/699/L139 : Spectral parameters of SNe Ia (Wang+, 2009)
J/A+A/523/A7 : Light curves of type Ia supernovae in SNLS (Guy+, 2010)
J/AJ/143/126 : Spectroscopy of 462 nearby TypeIa supernovae (Blondin+,2012)
J/ApJ/745/74 : Pre-maximum spectra of type Ia SNe (Folatelli+, 2012)
J/MNRAS/425/1789 : Berkeley supernova Ia program. I. (Silverman+, 2012)
J/A+A/554/A27 : 2011fe spectrophotometric time series (Pereira+, 2013)
J/other/Sci/340.170 : Classifications of 188 SNe Ia (Wang+, 2013)
J/A+A/568/A22 : Joint analysis of the SDSS-II & SNLS SNe Ia (Betoule+, 2014)
J/MNRAS/444/3258 : Velocities and EW of PTF SNe Ia (Maguire+, 2014)
J/MNRAS/448/2766 : Strong lines in the optical/NIR for SN2002bo (Blondin+,2015)
J/A+A/578/A9 : Optical and NIR spectra of SN iPTF13ebh (Hsiao+, 2015)
J/MNRAS/459/3939 : Type II supernova light curves (Valenti+, 2016)
J/ApJ/876/85 : HST observations for LMC Cepheids (Riess+, 2019)
Byte-by-byte Description of file: tablea1.dat
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Bytes Format Units Label Explanations
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1- 7 F7.1 d MJD [58605/58723] Modified Julian date of observation;
MJD-2400000.5
9- 15 F7.4 mag Umag [13.7425/17.3706]? The U band magnitude
17- 22 F6.4 mag e_Umag [0.0125/0.2996]? The one sigma error in Umag
24- 30 F7.4 mag Bmag [14.0571/18.2981]? The B band magnitude
32- 37 F6.4 mag e_Bmag [0.006/0.2658]? The one sigma error in Bmag
39- 45 F7.4 mag Vmag [13.9958/17.9068]? The V band magnitude
47- 52 F6.4 mag e_Vmag [0.0044/0.0661]? The one sigma error in Vmag
54- 60 F7.4 mag gmag [13.9363/17.9154]? The g band magnitude
62- 67 F6.4 mag e_gmag [0.0039/0.0323]? The one sigma error in gmag
69- 75 F7.4 mag rmag [13.9681/18.7994] The r band magnitude
77- 82 F6.4 mag e_rmag [0.004/0.0359] The one sigma error in rmag
84- 90 F7.4 mag imag [14.6078/19.0979]? The i band magnitude
92- 97 F6.4 mag e_imag [0.0046/0.0471]? The one sigma error in imag
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History:
From electronic version of the journal
(End) Prepared by [AAS], Coralie Fix [CDS], 29-Sep-2021